CVE-2023-41335
CVE-2023-41335 is a low-severity vulnerability in Matrix Synapse with a CVSS 3.x base score of 3.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-312.
Key facts
- Severity: Low (CVSS 3.x base score 3.7)
- EPSS exploit prediction: 0% (28th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-312
- Affected product: Matrix Synapse
- Published:
- Last modified:
Description
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer duration. These temporarily stored passwords are automatically erased after a 48-hour window. This issue has been addressed in version 1.93.0. Users are advised to upgrade. There are no known workarounds for this issue.
Frequently asked questions
- What is CVE-2023-41335?
- Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer duration. These temporarily stored passwords are automatically erased after a 48-hour window. This issue has been addressed in version 1.93.0. Users are advised to upgrade. There are no known workarounds for this issue.
- How severe is CVE-2023-41335?
- CVE-2023-41335 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over local access with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2023-41335 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-41335?
- CVE-2023-41335 primarily affects Matrix Synapse. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-41335?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2023-41335 published?
- CVE-2023-41335 was published on 2023-09-27 and last updated on 2026-06-17.
References
- https://github.com/matrix-org/synapse/pull/16272
- https://github.com/matrix-org/synapse/security/advisories/GHSA-4f74-84v3-j9q5
- https://lists.fedoraproject.org/archives/list/[email protected]/message/2AFB2Y3S2VCPCN5P2XCZTG24MBMZ7DM4/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/65QPC55I4D27HIZP7H2NQ34EOXHPP4AO/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/N6P4QULVUE254WI7XF2LWWOGHCYVFXFY/
- https://security.gentoo.org/glsa/202401-12
Affected products (3)
- cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
More vulnerabilities in Matrix Synapse
- CVE-2019-18835 — Critical (CVSS 9.8): Matrix Synapse before 1.5.0 mishandles signature checking on some federation APIs. Events sent over /send_join,…
- CVE-2024-53863 — Critical (CVSS 9.1): Synapse is an open-source Matrix homeserver. In Synapse versions before 1.120.1, enabling the dynamic_thumbnails option…
- CVE-2018-16515 — High (CVSS 8.8): Matrix Synapse before 0.33.3.1 allows remote attackers to spoof events and possibly have unspecified other impacts by…
- CVE-2024-52805 — High (CVSS 7.5): Synapse is an open-source Matrix homeserver. In Synapse before 1.120.1, multipart/form-data requests can in certain…
- CVE-2024-37302 — High (CVSS 7.5): Synapse is an open-source Matrix homeserver. Synapse versions before 1.106 are vulnerable to a disk fill attack, where…
- CVE-2021-41281 — High (CVSS 7.5): Synapse is a package for Matrix homeservers written in Python 3/Twisted. Prior to version 1.47.1, Synapse instances…
All CVEs affecting Matrix Synapse →
Other CWE-312 (Cleartext Storage of Sensitive Information) vulnerabilities
- CVE-2022-43757 — Critical (CVSS 9.9): A Cleartext Storage of Sensitive Information vulnerability in SUSE Rancher allows users on managed clusters to gain…
- CVE-2021-36782 — Critical (CVSS 9.9): A Cleartext Storage of Sensitive Information vulnerability in SUSE Rancher allows authenticated Cluster Owners, Cluster…
- CVE-2020-9045 — Critical (CVSS 9.9): During installation or upgrade to Software House C•CURE 9000 v2.70 and American Dynamics victor Video Management…
- CVE-2026-31848 — Critical (CVSS 9.8): Nexxt Solutions Nebula 300+ firmware through version 12.01.01.37 uses the ecos_pw cookie for authentication, which…
- CVE-2025-65826 — Critical (CVSS 9.8): The mobile application was found to contain stored credentials for the network it was developed on. If an attacker…
- CVE-2025-34206 — Critical (CVSS 9.8): Vasion Print (formerly PrinterLogic) Virtual Appliance Host and Application (VA and SaaS deployments) mount host…
Browse all CWE-312 (Cleartext Storage of Sensitive Information) vulnerabilities →